Easy, simply add '?contents=1' to the URL as a querystring parameter.
e.g. http://contoso/default.aspx?contents=1
It will take you to the 'Maintenance: Web Part Page' from where you can remove the problematic WebPart(s).
Update (2013/02/07):
| URL | Description |
| ?contents=1 | Open web part |
| _layouts/settings.aspx | Site Settings |
| _layouts/user.aspx | Manage users for site |
| _layouts/create.aspx | Page to create content. (useful if you have a Silverlight problem) |
| _layouts/AreaWelcomePage.aspx | Welcome page settings |
| _layout/addgallery.aspx | Direct link to Silverlight creation page. |
| _layouts/storman.aspx | Storage metrics for your SharePoint site |
| /_catalogs/users/simple.aspx | User information list for all users in SharePoint. |
| _admin/CNTDBADM.aspx | Manage content databases. (Central administration) |
| _admin/ServiceApplications.aspx | Service Application settings. (Central administration) |
| _layouts/viewscopes | View search scopes. (Central administration) |
| Generalapplicationsettings.aspx | General application settings. (Central administration) |
Thnx to:
http://technicallead.wordpress.com/2012/07/20/good-to-knowlayout-pages-in-sharepoint-2010/
